21 by Mark Mason

Explain that you went to a casino the other night to play blackjack. You show two cards, both black 9's.The cards are squared up and when shown again they turned into two red 10's!Next the 10's of Diamonds suddenly changes into a black Ace which can be handed out for examination.Now, turn the remaining card face-up, you have a BLACKJACK! Six changes from two cards! Precision-made gimmick does all the work! The backs and fronts are shown on every change!